package Text;

public class Text4 {
    public static void main(String[] args) {
        double b=0;
        for (double i=1;i<=100;i++){
            b+=shu(i);
        }
        System.out.println(b);
    }
    static double shu(double i){
        double b=0;
        b=1/i;
        if(i%2==0){
            b=-b;
        }
        return b;
    }
}
